21302688577 has 2 divisors, whose sum is σ = 21302688578. Its totient is φ = 21302688576.

The previous prime is 21302688553. The next prime is 21302688607. The reversal of 21302688577 is 77588620312.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 20783258896 + 519429681 = 144164^2 + 22791^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21302688577 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21302688577.

It is not a weakly prime, because it can be changed into another prime (21302688677) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10651344288 + 10651344289.

It is an arithmetic number, because the mean of its divisors is an integer number (10651344289).

Almost surely, 2^21302688577 is an apocalyptic number.

It is an amenable number.

21302688577 is a deficient number, since it is larger than the sum of its proper divisors (1).

21302688577 is an equidigital number, since it uses as much as digits as its factorization.

21302688577 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1128960, while the sum is 49.

The spelling of 21302688577 in words is "twenty-one billion, three hundred two million, six hundred eighty-eight thousand, five hundred seventy-seven".